72 air condition convert to r134a

[3li9]

hi
i own an 72 truck with bigblock from factry and air conditioning but it don t works.
now i decided to convert to r134a because in europe it s the only gaz i can find easyily.

does anyone has an idea what i have to change for this convertion?
does it exists a bolt on kit?

thanks a lot greetings frm germany

andy

[truckster]

There are kits available that contain adapters for your ports and a fill tube.

I would highly recommend you drain the AC components and clean them with solvent before you put in the PAG oil, since it's not compatible with the old stuff.

[mrein3]

Originally Posted by 3li9

hi
i own an 72 truck with bigblock from factry and air conditioning but it don t works.
now i decided to convert to r134a because in europe it s the only gaz i can find easyily.

does anyone has an idea what i have to change for this convertion?
does it exists a bolt on kit?

thanks a lot greetings frm germany

andy

Andy,
No problem converting what you have to work with R134a. I have done it and it works good.

The write up I did is here:
http://67-72chevytrucks.com/vboard/s...d.php?t=478564
Since you're starting with an AC truck you can skip the firewall conversion I had to do and the hole cutting in the dash. Scroll down to post #8 for a list of parts. I'd still buy the new hoses even if the ones you have are still on the truck. I've read that the older hoses aren't able to contain R134a. Since I was starting from scratch I didn't investigate that.

New hoses or not for SURE you want to get a new receiver/dryer. They are cheap here and easy to come by. I don't know about the price and availablity in Europe. When you get ready to charge the system you pull a vacuum. This vacuum boils the water out of the system as moisture will kill an AC system fast. The receiver/dryer contains a dessicant that removes any moisture that manages to get in the system. An old one that has been open to the environment for ANY amount of time is junk.

autoacforum used to have a really nice link on how to adjust your POA with pictures that I linked in my post but the link no longer works. I did a quick search there for you and came up with:
http://www.autoacforum.com/messagevi...threadid=10924
No pictures in that link but it gives an overview on what to do with your POA. Basically you look in one end where you can see a set screw. You adjust that screw until you get the desired reading on your AC gauges.

I can't emphasize enough the need to change EVERY o-ring in the system. I neglected the schrader valves in my system and guess what? They leak.

Another thing I would consider is changing out your condenser for a more modern condenser designed to work with R134a. R134a isn't as efficient at cooling as R12 so those old, large tubes in your stock condenser will work but not as good as a newer one. When I open my system this spring to work on those schrader valves I want to find a newer condenser that will bolt on the truck and connect to my system.

I hope this helps.

Matt

[3li9]

Thx for the reply s

i go the way in buying all hoses dryers and the other stuff new o rings all...
The compressor too so i will don t have problems with r134a...
Will post pictures soon but the parts take weeks to come to me
So it will take a while.